Reciprocating pump assembly



April 15, 1952 EL ROY J. KRAFT 2,593,316

RECIPROCATING PUMP ASSEMBLY Filed neo. 23, 194e -2 SHEETS-SHEET 1 April15, 1952 EL ROY J. KRAFT 2,593,316

RECIPROCATING PUMP ASSEMBLY Filed nec. '23, 194e 2 SHEETS- SHEET 2 lll/1|r///////////////,

INVEN TOR.

ATTYS.

Patented Apr. 15, 1952 UNITED` STATES PATENT OFFICE RECIPROCATING PUMPASSEMBLY El Roy J. Kraft, Oak Park; Ill., assignor to The Dole ValveCompany, Chicago, Ill., a corporation of Illinois Application December23, 1946,Y Serial No. 717,953

1 Claim.

' in the feed conduit to the pump when the valve is closed, and arrangedto eject pressured uid from this surge into the pump as soon as thevalve is opened.

Surge chamber arrangements to steady the discharge of reciprocatingpumps are known, but heretofore surge chambers have always been on thedischarge side of a reciprocating pump. According to this invention thesurge chamber is provided on the intake side of a fast-operatingreciprocating pump, not for the purpose of steadying the intake feed tothe pump, but for the purpose of greatly increasing the capacity andpumping rate of the pump.

This invention provides an arrangement which momentarily absorbs thesurge of liquid in the feed conduit to a reciprocating pump when theintake of the pump is closed during the pressuring cycle of the pump,and builds -up inlet pressure from-the kinetic energy of the flowingfluid for ejecting the pressured fluid into theinlet as soon as it isopened on the suction intake cycle of the pump.

Suitable surge chamber arrangements for carryingout the principles ofthis invention can take any one of a number of different forms. Forexample, a resiliently expansible hose section can be included in theintake conduit to the pump, a rigid hydraulic ram chamber can beprovided on the intake conduit supplying the pump, or a spring-pressedpiston slidably mounted in an expansion chamber communicating with theintake conduit for the pump can be used. The hose section will swell updue to the surge of liquid upon cessation of flow to the pump, therebymomentarily storing a slug of liquid under pressure adjacent the pumpinlet for forced ejection into the pump on the next cycle of operation.The hydraulic ram chamber will be filled with air that is compressedwhen the surge of liquid causes some liquid to flow into the chamber,and the compressed air back of the liquid is eective to eject it intothe pump on its next cycle of operation. The spring-pressed pistonarrangement I in an expansion chamber functions by receiving liquidforced into the chamber during the surge upon cessation of intake ilow,and by pushing this liquid into the intake of the pump on its next cycleof operation.

A feature of the invention resides in the provision of a veryfast-acting and eillcient intake check valve for the pump. This checkvalve closes instantaneously upon change of the pump cycle from suctionintake to pressure discharge so that flow of fluid in the intake conduitis instantaneously stopped, thereby enhancing thel surge of fluid tocreate a greater pressure buildup from the kinetic energy thereof.Conversely, the intake valve opens immediately upon change of thepressure cycle to the suction cycle of the pump and makes possible theimmediate utilization of the inlet pressure built up in the surgechamber arrangement.

Another feature of the invention resides in the provision of a surgechamber on the intake side of a pump having an interrupted intakeoperating through high speed cycles to develop kinetic energy inliquid'ilowing to the intake with a sufflcient momentum to tend tomaintain a con-- tinued ilow while absorbing the flow or surge into thesurge chamber during those portions of the interrupted flow cycle of thepump. l The high speed of the pumps of this invention'tends to build upa wave motion in the intake flow and the surge chamber absorbs thecrests of the waves to utilize their force for ejecting the liquid intothe pump on the next open cy-cle thereof.

. It is, then, an object of this invention to pro-` vide a device havingan interrupted flow intake with a surge chamber on the intake sidethereof arranged to build up inlet pressure from the kinetic energy ofthe flowing fluid.

` Another object of the invention is to provide a reciprocating pumpassembly with a surge cham.

ber on the intake side thereof. t

A further object of the invention is to provide a device having aninterrupted fluid intakeV cycle with -a check valve operating inresponse to cycle conditions and means in advance of the valve forbuilding up inlet pressure, `when the valve .is4 closed, from thekinetic energy of fluid ilowing. to the valve and for ejecting thepressured fluid said passageway.

ber slidable on the body member and having an end face with an axialopening therein for receiving fluid from the passageways when the endface is spaced from the body member and for sealing the passageway whenthe end face iS against the body member.

A still further object of the invention is to provide a check valve forpumps and the like composed of a disk with a thickened central -portionhaving a plurality of passageways therethrough arranged in spacedrelation from the axis thereof, together with a metal cap'memberslidable on the thickened portion of the disk and carrying a sealingliner for coacting with the end face of the thickened portion to closeOther and further objects of the invention will be apparent to thoseskilled in the art from the following detailed description of theannexed sheets of drawings which, by way of preferred examples only,illustrate several embodimentsof the invention.

AO n the drawings:

Figure l is an end elevational view of a pump assembly according to thisinvention.

Figure 2 is a vertical cross-sectional view, with parts in sideelevation, taken along the line II-II of Figure 1, and showing theintake cycle of the pump assembly.

Figure 3 is a fragmentary view similar to Figure 2, but illustrating thedischarge cycle of the pump- Figure 4 is a View similar to Figure 3 butillustrating a hydraulic ram surge chamber arrangement in place of theresiliently expansible hose section.

Figure 5 is a View similar to Figure 3 but illustrating an expansionchamber having a springpressed plunger in place of the expansible hoseof Figure 3 and the hydraulic' ram of Figure 4.

Figure 6 is an enlarged axial cross-sectional View of the check valve inthe pumps of Figures 1 to 5.

Figure 7 is a plan View of the body of the check valve.

Figure 8 is a plan View of the cap member of the valve.

Figure 9 is a plan view of the sealing liner for the cap ofthe valve.

As shown on the drawings:

In Figures 1 and 2, the reference numeral I3 designates generally a pumpassembly according to this invention. Anl electric motor II is providedfor driving the pump and, for this purpose, has ashaft I2 projectingtherefrom and carrying an eccentric I3. A bearing I4 surrounds the Yeccentric and a strap member I5 surrounds the bearing. The strap memberhas a slot I5a in the top end thereof providing furcated arms whichreceive aligned bearing sleeves I6. A cross pin I1 is mounted in thesleeves I6.

A frame or bracket I8 is secured on the end of the motor I I and has aboss portion I9 carrying a bearing overlying the strap I5. A pump piston2lV is slidably mounted in the bearing 26 and Vhas an eye end 2I a inthe slot 15a of the strap and receiving the cross pin I1 therein. Thecross pin is locked in the eye end of the piston by means of a pin 22.

The bracket I8 has a cylindrical pump housing 23 on .the upper endthereof above the boss I9.

This Vhousing 23 has a well 24 extending upwardly from the bottomthereof and receiving packing rings 25 therein. The piston 2| slidesthrough the rings 25 into the pump bore 26. The piston fits freely inthe bore 26 and operates to displace fluid therefrom. A packing plate 21extends into the well 24 and is urged against the bottom packing ring 25by means of bolts 28 extended through a ange 21a of the plate 21 andthreaded into ther bosses 23a on the pump housing 23. These screws 28are tightened to force the member 21 into the well thereby compressingthe packing material 25 and maintaining a leakproof seal around thepiston 2|. I l

The body23 has a side nipple 29 providing an intake port for the pumpbore or chamber 26.

The nipple 29 has a stepped bore therethrough including an Vinternallythreaded outer end portion 36, a first .shoulder 3I, a first restrictedbore portion 32., a second shoulder 33. a second restrcted bore portion34. and a blind bore portion 35 of smaller diameter than the portion 34.Passageways 36 join the `bottom of the blind bore 35 with the interiorof the pumping chamber 26. The pumping chamber thereby has a sideintake.

An intake check valve 31; has the body portion 38 thereof bottomed onthe shoulder 3l, and has the cap portion 39 thereof confined formovement Within the bore portion 32 because the shoulder 33 limits themovement of the cap 36 off of the body. A coil spring 40 is bottomed onthe blind bore portion 35 and acts on the cap 39. A hollow fittingmember 4I is threaded into the portion 36 of the bore and is internallythreaded for receiving a hose nipple 42 in threaded relation therein.This nipple 42 has a bulbous portion 42a near the kend thereof. A rubberhose 43 is stretched over the fitting 42 around the bulbous portion 42athereof and a hose clamp 44 secures the hose on the fitting. Y

The top of the housing 23 has a well 45 therein and a second check valveassembly 46, identical with the assembly 31, has the body portionthereof seated in the lbottom of the well. A hollow fitting member 41 isthreaded into the well 45 against the body of the check valve 46 andVhas a stepped bore therein providing a chamber for the cap member ofthe valve as well as an abutment for the spring of this cap member.discharge conduit 48 is threaded into the tting 41. l

The eccentric I3 rapidly reciprocates the piston 2| in the pump chamber26 from the suction intake position shown in Figure 2 to the pressuredischarge position shown in Figure 3. On the intake, or downstroke,shown in Figure 2liquid from the hose 43 is sucked into the pumpingchamber 26 through the inlet passages 36. On this suction stroke, thecap member 39 of the intake check lvalve 31 is drawn against theshoulder 33 thereby allowing fluid fiow through the check valve.A

As best shown in Figures 6 to 9, the check valve 31 has the body member38 thereof in the form of a circular disk. A thick cylindrical centralportion 38a of reduced diameter is formed integrally onthe disk andprojects from one face thereof. vThis thick portion 38a has aflat endface 38h. The lcap member 39 of the valve 31 has a circular end wall 39awith a cylindrical skirt 39h projecting therefrom and slidable on thecylindricalv thick portion 38a of the disk. The cap 3.9 has a liner disk43 composed of rubber, fiber. plastic, or the like in the cylindricalskirt 39h thereof andibottomed on the end wall 39a.

The body member 38 has a plurality of longitudinal passages 3.80extending through the thick portion .38a thereof inradially,spacedrelation from the axis of the body. As shown in Figure 7,sixpassage's 38C are provided' and they are equally spaced around theaxial center of the body. f i

The cap member 39 has an aperture 39c in its end face 39a thereof at theaxial center of the cap. An aligned aperture 49a is provided in thesealing disk liner 49.

vWhen the liner 49 is bottomed on the end face 38h of the body member,the passageways 38e are'effectively sealed. However, when the cap member33 is moved to carry the liner 49 thereof away from the end face 381), aiiow path is opened up between the passage 38e and the apertures 49a`and 39C.A thereby accommodating fluid flow through the check assembly.The skirt 39h, in riding on the cylindrical portion 38a of the body 38,prevents cooking of the cap and insures full seating of the liner on theend face 38h whenever the valve is closed. The valve is very rapid inoperation, has relatively high capacity for its size, and can be madevery light in weight to eliminate heretofore-encountered inertia incheck valve assemblies. As soon as the liner of the valve is cracked oiiof the end face of the body. fluid will rapidly iiow through the valve,andfconversely, as soon as this liner is pressed against the end face,all ow through the valve is-stopped.` Y

The pumping chamber 26 is filled with liquid on the intake stroke. shownin Figure 2, and the eccentric then reversely reciprocates the piston i2 ly to pressure the liquid in the pumping chamber and eject it from thepump. As shown in Figure 3, as soon as the piston starts on itsupstroke, the check valve 31 is closed and the check valve 46 is opened.Liquid in the pumping chamber 26 is thereby forced through the checkvalve 46 and into the discharge conduit 48.

The piston 2| is reciprocated very rapidly, so that the pump goesthrough its suction and discharge cycles at very high speed. During theintake or suction cycle of the pump liquid in the hose 43 flows ratherrapidly because of the high speed of operation of the pump, and theflowing liquid builds up considerable kinetic energy. As soon as theintake valve 31 closes. however, the liquid, due to its kinetic energyand momentum, will produce a surge which, unless dissipated, wouldproduce a water hammer effect in the intake pipe 56. According to thisinvention, however, the water hammer effect is entirely eliminated andthe hose section 43 between the pipes 50 and intake fitting 42 issuiiiciently yieldable so that it will expand to the position shown inFigure 3 thereby providing an enlarged chamber accommodating the surgeof liquid. Of course expansion of the hose occurs by its ability toresiliently stretch, and, in its stretched psition, the hose materialsuch as rubber, is tensioned or loaded and will assume its untensionedor unloaded condition as soon as permitted. Thus, when the intake valve31 is again opened on the next suction stroke yof the pump, the liquidfilling the stretchedV hose will be immediately expelled under thepressure developed by the tensioned or loaded condition of the hose andwill be effectively forced into the pump chamber. As a result,therefore, charging of the pump on its suction stroke is speeded up andmade easier because the liquid is actually injected into the pumpinstead of being drawn against the usual frictional drag occurring in anintake conduit.

The hose section 43 should be positioned immediately adjacent the intakeof the Dump and, of course. should be resiliently expansible to Jde- 6velop a tensioned pressure-producing condition. The hose section shouldbe sufficiently short so that the surge chamber effect is obtainedwithout dissipating the kinetic energy of the iiuid.

In effect, the cycle reversals of the pump of this invention occur sorapidly that fluid flow in the conduit 50 is never completely stopped,

and a wave motion is built up the crests of 'which` are absorbed in theexpansion of the hose to forcibly expel the liquid as soon as the intakevalve is open.

The pump l0, instead of being equipped with the rubber hose intakearrangement of Figures 1 to 3 can, according to a modied embodiment ofthis invention, have an intake pipe 5l with a hydraulic ram 52 thereondefining a surge cham-'- ber 53 which is normally filled .with air. Onthe suction stroke of the pump, liquid iiows rapidly through the pipe#5i to build up an appreciable kinetic force. Upon reversal of the cycleof Vthe pump to the discharge stroke, the valve 31 closes, and thekinetic energyAor momentum of the fluid in the pipe 5i causes some fluidto flow into the chamber 53 of the hydraulic ram thereby com pressingthe air therein. This compressedair,

acting directly on theiiuid in the chamber 53,

thereupon effective to eject the iiuid out of the chamber and into thepumping chamber 36 on4 the next suction stroke of the pump. The cyclereversals of the pump are so rapid that the hydraulic ram will absorbthe surges of uidoccurring during the pressure strokes of the pumpWithout stopping flow of the liquid in the pipe 5I and, at the sametime, the kinetic energy in the surges is salved for ejecting the iiuidduring the next suction cycle of the pump.

In the embodiment of the invention shown in Figure 5, the pump I8 isequipped with a rigid, non-expansible inlet pipe 60 having a flangednipple l6| thereon closely adjacent the pump inlet. This nipple 6Idefines a cylindrical bore 62 in communication with the interior of thepipe 60. A housing 63 is secured on the flanged nipple 6I by means ofbolts 64 and has a large bore 65 therein aligned with the` bore 62 andof substantially the same diameter together .with a small bore 66extending upwardly from the upper end of the bore 65. A vent 61 joinsthe upper end of the bore 66 with the surrounding atmosphere. A pistonhead 68 is slidably mounted in the bores 62 and 65 and has an integralrod or stem portion 69 slidable in the bore |66. A coil spring 10 isheld under compression between the bottom of the bore and the pistonhead 68 to urge the piston head toward the interior of the pipe 60. Ashoulder 1| in the bore 62 limits the in- -ward travel of the piston.

On the suction stroke of the pump I0, liquid, of course, flows throughthe pipe 60, and the spring 16 plus the intake suction holds the piston68 against its shoulder 1I. Immediately upon termination of the suctionintake stroke of the pump, the intake check valve 31, of course, closes.and the kinetic energy in the rapidly flowing liquid in the inlet pipe60 causes the liquid to surge against the piston 68 thereby forcing itupwardly in the bore 62 and compressing the spring 1D. Some liquid isthereupon momentarily stored in the bore 62 and is acted on by thespring-pressed piston which, of course, tends to force the liquid backinto the pipe 60. Therefore, on the next suction intake stroke of thepump il), the liquid is pushed by the piston 68 into the pipe 60 andthence, of course, into the pump inlet. The bore 62 and, if necessary,the bore 65 therefore define anfexpansionchamber' absorbing the'fsurgeof liq# uid-. caused lb'y :cycle freversals of fthe.'` pump 1f and i1.

utilizngfthe .-'energyiofY th'e 1 surgev =to` gloadza spring i forexpelling" the :liquid `on: the next .intake stroke of. .the pumpi Thethree `embodiments of theinventionillus'.-

trated'ghereir show vthe 'useE of dierentk typespoff:

surge :chambers .fon the` intake side of a recipro catinggpumpforabsorbing a surge of liquidnupon reversal of thel pump cycle from:intake` tozcomz pression, and for ejecting the absorbed liquid underlpressure Iduring :the next intake stroke 'of surge'chambers.a'bsorbingthe crests ofy the waves cee'ding. suction stroke ofthe pump.

.-20.2 to:z-utilizefthey kineticv energy` therein on r,the sucl detailsof Iconstructionmay'be varied through as widerange-without 'departingfrom the principles of;this#inventionA and it is,:. therefore,v not'thev. purpose tolimitpthe patent granted hereon otherf wisethanmecesstat'ed bythe scope of theapjpendediclaimp.

. I-claimrasmygnvention:

Aareciprocatingfpumpcomprising1.a pump body havingf an. open-,endedpumpingjchamber havV ingaicylindricallwall', ailuid inlet leadingthroughsaid/wall `into saidA chamber, a'V lightweight .valve ,Y

disk Y assemblyL including; a .disk freciprocable inaapistonmovablewithin said chamber-and extendihgsfrom' one-open endvthereof. .said other openflend Lof 1 the .chamber providingps, fluidoutleal-alcheckfvalvem `said otheropen end, an out-.1- letittin'gfanchoringsaid checkzvalvein said' out- V35.52 said inlet tocheck back-flow fromthefchamber,

lett', an .eccentric pperatiuely;connecteckwithfsaid;piston;tor:reciprocably.fmovesesadl pistonnwithnw. y

said pumping chamber, an inlet fitting anchoring;` said valvediskassemblyin said inlet',iianda..nipp lje carriedzbyfsaid iinlettting;'ar-short elastic Ltubes.l

onY said nipple ;.forming af r contmuatio'n thereof.;r

tractble :immediate1y;-adjacent..the fnipple-:toia'b sorbsurgesiin said:inlet when the disk.;va1ve'c1oses;; andxtoff. force f'. .vuid f. into.,said; pumping.; chamber". f

REFERENGES'iCITED.

The -foil'wing :references fare EOf-ecOrdi'Jinfithel:

Number Name Date- 57,412 /Veydei ,.Aug.- 21,.,1866v 2104,7-.471' Maxim--,.June:f11; 187:82 852,150.. WhitneyKA Apr. 30511907:v 912,502'1 Squiresf .Feb. 16,; 1909..l 1,075,322 Bargamin .f Oct...14;...1913 s 1,129,072Conn 1; LEeb.23,-119151,- 1,204,898 Nichols Nov..14;..19.16 1,266,650:Brandenberger x MaygZ l, v1918 1,713,073 Carter; li/lay,145;.1929.1A1,865,000e f Goldberg@ June. .248, ,1932 1,944,340, Zubatygehal;,.Jan;-.23',1934:t 1,979,479 Labaw ..Nov.f 631934.15 2,008,133f. Farmer.,July=16, `1935'w 2,261,948'.. Beach -.Nov.1 11, ,194115. 2,325,672Groff ...Aug3, 19431.

FOREIGN PATENTS Number` Country` Date 18,106 Norway .....l)"ec.`14,;190'1.`v

